1.5-foot Gregorian reflecting telescope for equatorial mount
Date: 1788-1800
Inventory Number: 0056b
Classification: Telescope
Supplier: the Reverend John Prince (1751 - 1836)
User: Joseph Willard (1738 - 1804)
Cultural Region:
Dimensions:
9.9 × 11 × 54 cm (3 7/8 × 4 5/16 × 21 1/4 in.)
Material:
Bibliography:
The Apparatus of Science at Harvard, 1765-1800
Description:
This additional telescope for the George Adams universal equatorial mount (0056) is a Gregorian reflector supplied by Dudley Adams. The brass tube has its eyepiece, primary and secondary mirrors, and long focusing screw controlled by a knurled knob. The dust cap is missing. The focal length is about 16 inches, and the aperture about 3 1/4 inches.
The finder device consists of a pinhole sight near the eyepiece and a triangular pointer at the other end of the tube.
The tube is mounted in two brass cradles, which can be secured to the equatorial mount. These cradles are very chunky.
The finder device consists of a pinhole sight near the eyepiece and a triangular pointer at the other end of the tube.
The tube is mounted in two brass cradles, which can be secured to the equatorial mount. These cradles are very chunky.
In Collection(s)
Signedunsigned
Historical AttributesThe Reverend John Prince sold this reflecting telescope with an equatorially mounted refractor to Harvard in 1803.
In a letter to President Joseph Willard, dated 14 February 1803, Prince described the instrument as second hand, but as good as new. The equatorial mount and refractor were made by George Adams for a gentleman who died abroad and originally cost 75 guineas. The reflecting telescope and magnetic compass were added by Dudley Adams for an additional 5 guineas. Dudley Adams told the purchaser that "he would not undertake to make one like it, of this size and construction, with all its adjustments, [for] under 100 Guineas."
Prince offered the mounting with the two telescopes to Harvard for "ye moderate price of 300 doll[ar]s, which is not ye first cost of it by more than 70." He remarked that Harvard's President and Fellows "perhaps...never will have so good an opportunity of purchasing so valuable an instrument of this kind so cheap--As ye equatorial is ye only instrument, which describes ye path of ye heavenly bodies it is very useful for instruction in astronomy, and is perhaps ye best for illustrating ye principles of dialling--I am desirous of see[in]g: it placed in ye apparatus of ye university, as such capital instruments give importance to it abroad."
Prince however struck a deal. He offered "to take ye old standing airpump, with ye parts necessarily connected with it...in part payment for ye equatorial and to allow 100 doll[ar]s for them, which I think [a very] generous price considering ye state of ye pump...[which] will require considerable trouble and exp[ense to] reduce it to ye simple form...in which way only it can be useful to any one."
The Harvard Corporation agreed to the deal, paying Prince "two hundred dollars in cash... [plus] the old Air Pump belonging to the Apparatus."
In a letter to President Joseph Willard, dated 14 February 1803, Prince described the instrument as second hand, but as good as new. The equatorial mount and refractor were made by George Adams for a gentleman who died abroad and originally cost 75 guineas. The reflecting telescope and magnetic compass were added by Dudley Adams for an additional 5 guineas. Dudley Adams told the purchaser that "he would not undertake to make one like it, of this size and construction, with all its adjustments, [for] under 100 Guineas."
Prince offered the mounting with the two telescopes to Harvard for "ye moderate price of 300 doll[ar]s, which is not ye first cost of it by more than 70." He remarked that Harvard's President and Fellows "perhaps...never will have so good an opportunity of purchasing so valuable an instrument of this kind so cheap--As ye equatorial is ye only instrument, which describes ye path of ye heavenly bodies it is very useful for instruction in astronomy, and is perhaps ye best for illustrating ye principles of dialling--I am desirous of see[in]g: it placed in ye apparatus of ye university, as such capital instruments give importance to it abroad."
Prince however struck a deal. He offered "to take ye old standing airpump, with ye parts necessarily connected with it...in part payment for ye equatorial and to allow 100 doll[ar]s for them, which I think [a very] generous price considering ye state of ye pump...[which] will require considerable trouble and exp[ense to] reduce it to ye simple form...in which way only it can be useful to any one."
The Harvard Corporation agreed to the deal, paying Prince "two hundred dollars in cash... [plus] the old Air Pump belonging to the Apparatus."
Published ReferencesDavid P. Wheatland, The Apparatus of Science at Harvard, 1765-1800 (Cambridge: Harvard University Press, 1968), 26-29, 111.
